JP2000045244A - Water quality purifying bank and water intake method from its internal water area - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure a reciprocating current of sea water even at the time of taking in water from an internal water area. SOLUTION: A water quality purifying bank 11 is formed in a circular arc shape and constructed so as to separate a sea area extending in the neighbourhood of a land 12 into an external water area 5 and an internal water area 6 by connecting its both ends to the land 12. In this case, the water quality purifying bank 11 is under a premise to take in water of the internal water area 6 to use it for an optional purpose, for example, as industrial water, and the water quality purifying bank 11 is constructed so that an area A of the internal water area 6 becomes A>Q.T/H at the time when it is specified that water intake quantity per hour is Q, time from high tide to low tide is T and a tidal range is H at that time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water purification levee constructed so as to surround a desired purified water area and a method for withdrawing water from the inner water area.

[0002]

2. Description of the Related Art In order to secure a hydrophilic space rich in amenity in a waterfront, it is essential to purify water to form a favorable water environment. Have been.

As shown in FIG. 4, a water purifying embankment 1 is obtained by stacking embankment members 2 made of gravel or crushed stone in a substantially trapezoidal shape from the seabed 3 and covering the same with a predetermined covering stone 4. If constructed so as to surround the water area, the internal water area 6 of clean water quality can be created by the water purification function of the natural ecosystem.

That is, when shifting from low tide to high tide,
The seawater in the outer water area 5 moves to the inner water area 6 through the gap between the embankment members 2 of the water purification levee 1, and at this time, pollutants such as plankton contained in the seawater are deposited on the surface of the embankment member 2. It is attached or trapped by a biofilm composed of attached microorganisms, and is further ingested and removed by shellfish and crustaceans living between gravel.

On the other hand, the flow in the reverse direction from high tide to low tide prevents clogging of the embankment material 2 without requiring artificial maintenance, and the reciprocating flow causes water exchange in the inland water area 6. Is also possible.

[0006]

In order to maintain the natural purification function of the water purification levee 1 as described above, a reciprocating flow utilizing the ebb and flow of the tide is indispensable. For example, when water is taken from the inner water area 6 as industrial water, when shifting from high tide to low tide, seawater that would otherwise flow from the inner water area 6 to the outer water area 5 as shown in FIG. If the water intake (water intake speed) is too large, the water does not flow into the external water area 5 as shown in FIG.
A problem of backflow.

[0007] Such a problem causes the flow of seawater to always be in one direction, causing clogging of the embankment material 2 and deteriorating the water exchange function and the natural purification function.

The present invention has been made in view of the above circumstances, and provides a water purification levee capable of securing a reciprocating flow of seawater even when drawing water from an inland water area, and a method of withdrawing water from the inland water area. The purpose is to provide.

[0009]

According to a first aspect of the present invention, there is provided a water purification purifier constructed by stacking embankment materials.
When the amount of water withdrawn from the inland water area per hour is Q, the time from high tide to low tide is T, and the tidal difference is H, the area A of the inland water area
Are constructed so that A> Q · T / H.

[0010] The water purification dike according to the present invention is defined in claim 2.
As described in the above, the water purification purifier constructed by stacking the embankment material, is provided with a water intake facility capable of withdrawing water from the inland water area, and the water intake equipment is provided with the area of the inland water area A, from high tide to low tide. When the time is T and the tidal difference is H, the water intake Q per time is such that Q <A · H / T.

Further, in the method for withdrawing water from the inner water area of a water purification purifier according to the present invention, the area of the inner water area of the water purification purifier constructed by stacking the embankment material is defined as A, from the high tide. Assuming that the time until the low tide is T and the tide difference is H, the water intake Q per hour from the inland water area is limited to Q <A · H / T.

[0012] In the water purifying embankment and the method of withdrawing water from the inner water area according to the present invention, the amount of water taken per hour from the inner water area of the water purifying embankment constructed by stacking the embankment material is Q, and the water amount is from high tide to low tide. When the time is T, the tidal difference is H, and the area of the inland water area is A, these are A> Q · T / H or Q
<Area A of the inland waters so as to satisfy the relationship A · H / T
Or limit the amount of water withdrawal Q per hour.

In this case, the water level descent speed Q / A in the inland water area from high tide to low tide is always lower than the water level descent rate H / T in the external water area. The flow of seawater going is secured.

The time T from the high tide to the low tide can be determined to be approximately 6 hours in design, but since the tidal power fluctuates complicatedly and does not have perfect periodicity, the time T
How to determine is arbitrary.

Regarding the tidal difference H, that is, the difference between the tide level of the high tide and the low tide, how to set this is optional.
If the minimum value is taken in consideration of the seasonal variation and geographical variation, it is possible to secure the reciprocating flow of seawater throughout the year. By the way, as the minimum value, it is conceivable to use the tide difference when the lunar tide rises or lowers when the lunar tide rises against the sun tide, that is, when the tide rises.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a water purification bank and a method for withdrawing water from its inner water area according to the present invention will be described with reference to the accompanying drawings. It is to be noted that the same reference numerals are given to components and the like that are substantially the same as those in the conventional technology, and description thereof will be omitted.

(First Embodiment)

FIG. 1 shows a water purification bank 11 according to this embodiment.
FIG. As can be seen from the figure, the water purification levee 11 according to the present embodiment is formed in an arc shape as a whole, and by connecting both ends thereof to the land 12, the sea area extending in the vicinity of the land 12 is connected to the outer water area 5 and the inner water area. It is constructed to be separated from the water area 6.

Here, the water purification levee 11 has an arbitrary purpose,
For example, it is assumed that the water in the inland waters 6 is taken in order to use it as industrial water. When the amount of water taken per hour at that time is Q, the time from high tide to low tide is T, and the tidal difference is H The water purification levee 11 is constructed so that the area A of the inner water area 6 satisfies A> Q · T / H.

The cross section of the water purification levee 11 is similar to the conventional water purification levee 1 described with reference to FIG.
The embankment material 2 is made of a material that has a biofilm attached thereto and can inhabit organisms such as shells, such as gravel, crushed stone, or concrete waste having a particle size of about 20 cm to 30 cm. be able to.

Here, the time T from high tide to low tide can be determined to be approximately 6 hours in design. Also,
As the tide difference H, that is, the difference between the high tide and the low tide, it is desirable to use the tide difference at the time of the ebb tide. By using the tidal range at the time of the ebb tide, it is possible to always maintain the reciprocating flow of seawater throughout the year.

In the water purification levee 11 according to the present embodiment, the amount of water withdrawn from the inner water area 6 per hour is Q, the time from high tide to low tide is T, the tidal difference is H, and the area of the inner water area is A. At this time, the area A of the inland water area 6 is secured so that these satisfy the relationship of A> Q · T / H.

In this way, the water level descent rate V ₂ = Q / A in the inland water area from high tide to low tide is always lower than the water level descent rate V ₁ = H / T in the external water area 5 as shown in FIG. In other words, the seawater in the inner water area 6 flows out to the outer water area 5 even during water intake in such a time zone.

As described above, according to the water purification levee 11 according to the present embodiment, the water level descent speed V ₂ = Q / A in the inland water region from high tide to low tide is equal to the water level descent speed V ₁ in the external water region 5. = H / T is always below, so even if you take only Q per hour during the period from high tide to low tide,
The seawater in the inner water area 6 flows out to the outer water area 5. On the other hand, during the time period from low tide to high tide, seawater flows from the outer water area 5 to the inner water area 6 regardless of the presence or absence of water intake.

Therefore, it is possible to ensure a reciprocating flow of seawater within the cross section of the water purification levee 11, and as a result, the clogging of the levee body material 2 is prevented beforehand, and a water exchange function and natural purification. The function can be maintained without maintenance.

(Second Embodiment)

Next, a water purification levee according to a second embodiment and a method for withdrawing water from its inner water area will be described. In addition, the same reference numerals are given to components and the like that are substantially the same as those in the above-described embodiment, and description thereof is omitted.

FIG. 3 shows a water purification wall 21 according to this embodiment.
FIG. As can be seen from the figure, the water purification levee 21 according to the present embodiment also
Similarly to the above, it is formed in an arc shape as a whole, and by connecting both ends to the land 12, the sea area extending near the land 12 is separated into the outer water area 5 and the inner water area 6.

The water purifying bank 21 is provided with a water intake 22 for taking water from the internal water area 6 for any purpose, for example, as industrial water. Is defined as A, the time from high tide to low tide is T, and the tidal difference is H, the water intake Q per time is Q <A · H / T.

In the water purifying embankment 21 and the method of withdrawing water from the inner water area according to the present embodiment, when water is withdrawn from the inner water area 6 through the water intake equipment 22, the amount of water Q per hour is Q.
Water intake is restricted so as to be <A · H / T.

[0031] Limiting in this way the water intake amount Q of intake facility 22, drawdown velocity V ₂ = Q / A in the inner waters from high tide to low tide, similarly to FIG. 2, the water level lowering speed V ₁ at the outer waters 5 = H / T, and the seawater in the inner water area 6 flows out to the outer water area 5 even during water intake in such a time zone.

As described above, according to the water purification wall 21 and the method of withdrawing water from the inner water area according to the present embodiment,
Water level descent rate in inland waters from high tide to low tide V ₂ =
Q / A is the water level descent speed V ₁ = H / T in the external water area 5
, The seawater in the inner water area 6 flows out to the outer water area 5 even if Q is withdrawn per hour during the period from high tide to low tide. On the other hand, during the time period from low tide to high tide, seawater flows from the outer water area 5 to the inner water area 6 regardless of the presence or absence of water intake.

Therefore, it is possible to secure a reciprocating flow of seawater within the cross section of the water purification levee 21, and as a result, the clogging of the levee body material 2 is prevented beforehand, and a water exchange function and natural purification are achieved. The function can be maintained without maintenance.

In the present embodiment, the water intake from the inland water area 6 is taken by the water intake equipment 22. However, even if the permanent water intake equipment 22 is not installed, the water intake means 22 may be provided via purified water conveying means such as a water truck. Alternatively, water may be taken from the inland water area 6. Even in such a case, the inland waters 6
If the amount of water taken from the water is limited, it is also possible to secure a reciprocating flow of seawater within the cross section of the water purification bank 21.

[0035]

As described above, according to the water purification levee and the method of withdrawing water from the inner water area according to the present invention, the seawater in the inner water area is not affected even when water is taken during the period from high tide to low tide. Since the water flows into the water area, it is possible to secure the reciprocating flow of seawater within the cross section of the water purification purifier, and as a result, clogging of the embankment material is prevented beforehand, and the water exchange function and the natural purification function Maintenance-free maintenance is possible.

[0036]

[Brief description of the drawings]

FIG. 1 is an overall plan view of a water purification purifier according to a first embodiment.

FIG. 2 is a sectional view showing the operation of the water purification bank according to the first embodiment.

FIG. 3 is an overall plan view of a water purification dike according to a second embodiment.

FIG. 4 is a cross-sectional view of a water purification bank according to the related art.

FIG. 5 is a cross-sectional view of a conventional water purification dike showing a flow of seawater when water is taken from an internal water area.

[Explanation of symbols]

 5 Outer water area 6 Inner water area 11, 21 Water purification dike 22 Intake facility

 ──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Hirokazu Tsuji 4-640 Shimoseito, Kiyose-shi, Tokyo Inside Obayashi Corporation Technical Research Institute, Inc. (72) Inventor Makoto Kobayashi 2-3-3 Kandajicho, Chiyoda-ku, Tokyo, Ltd. Obayashi Tokyo head office

Claims (3)

[Claims] Claims 1. In a water purification purifier constructed by stacking embankment materials, when the amount of water taken from an inland water area per hour is Q, the time from high tide to low tide is T, and the tidal difference is H, Area A
However, the water purification levee was constructed so that A> Q · T / H. 2. A water purification purifier constructed by stacking embankment members, comprising a water intake facility capable of withdrawing water from an inland water area, wherein the area of the inland water area is A, and the time from high tide to low tide. Where T is the tide difference and H is the tidal difference,
However, the water purification purifier characterized by having Q <A · H / T. 3. The amount of water withdrawn from the inner water area per hour, where A is the area of the inner water area, T is the time from high tide to low tide, and H is the tidal difference of the water purification levee constructed by stacking embankment materials. Q
Water intake from the inner water area of the water purification purifier, wherein the water intake is restricted to Q <A · H / T.